A smoke stopper can help avoid damage when you power on a mini quad drone for the first time. Sometimes you might have a defective part or a short somewhere, the smoke stopper can limit the current flow and prevent "magic smoke" It saves your electronic components from current surges, and gives you a chance to troubleshoot the failure without having to replace the burnt-out parts. The LED indicator will be green when the current is within 1.2A. The LED indicator turns off and starts beeping in abnormal situation. Main Features: * This smoke stopper can help avoid damage when you power on your 2-8s quad drone for the first time * XT90(Input and Output),suit for FPV drone with XT90 connector. Specification: Connector : XT90 (Input and Output) Trip current 1.2A